Electrosurgical pencil with improved controls

ABSTRACT

An electrosurgical pencil is provided which includes an elongated housing, an electrocautery blade supported within the housing and extending distally from the housing. The electrocautery blade is connected to a source of electrosurgical energy. The pencil also includes at least one activation switch supported on the housing which is configured and adapted to complete a control loop extending from the source of electrosurgical energy. At least one voltage divider network is also supported on the housing and is electrically connected to the source of electrosurgical energy.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a Continuation-in-Part Application claimingbenefit of and priority to International Application No. PCT/US03/37111,filed on Nov. 20, 2003, the entire content of which is incorporatedherein by reference.

BACKGROUND

1. Technical Field

The present disclosure relates generally to electrosurgical instrumentsand, more particularly, to an electrosurgical pencil having a pluralityof hand-accessible variable controls.

2. Background of Related Art

Electrosurgical instruments have become widely used by surgeons inrecent years. Accordingly, a need has developed for equipment andinstruments which are easy to handle, are reliable and are safe in anoperating environment. By and large, most electrosurgical instrumentsare hand-held instruments, e.g., an electrosurgical pencil, whichtransfer radio-frequency (RF) electrical or electrosurgical energy to atissue site. The electrosurgical energy is returned to theelectrosurgical source via a return electrode pad positioned under apatient (i.e., a monopolar system configuration) or a smaller returnelectrode positionable in bodily contact with or immediately adjacent tothe surgical site (i.e., a bipolar system configuration). The waveformsproduced by the RF source yield a predetermined electrosurgical effectknown generally as electrosurgical cutting and fulguration.

In particular, electrosurgical fulguration includes the application ofelectric spark to biological tissue, for example, human flesh or thetissue of internal organs, without significant cutting. The spark isproduced by bursts of radio-frequency electrical or electrosurgicalenergy generated from an appropriate electrosurgical generator.Coagulation is defined as a process of desiccating tissue wherein thetissue cells are ruptured and dehydrated/dried. Electrosurgicalcutting/dissecting, on the other hand, includes applying an electricalspark to tissue in order to produce a cutting, dissecting and/ordividing effect. Blending includes the function of cutting/dissectingcombined with the production of a hemostasis effect. Meanwhile,sealing/hemostasis is defined as the process of liquefying the collagenin the tissue so that it forms into a fused mass.

As used herein the term “electrosurgical pencil” is intended to includeinstruments which have a handpiece which is attached to an activeelectrode and which is used to cauterize, coagulate and/or cut tissue.Typically, the electrosurgical pencil may be operated by a handswitch ora foot switch. The active electrode is an electrically conductingelement which is usually elongated and may be in the form of a thin flatblade with a pointed or rounded distal end. Alternatively, the activeelectrode may include an elongated narrow cylindrical needle which issolid or hollow with a flat, rounded, pointed or slanted distal end.Typically electrodes of this sort are known in the art as “blade”,“loop” or “snare”, “needle” or “ball” electrodes.

As mentioned above, the handpiece of the electrosurgical pencil isconnected to a suitable electrosurgical energy source (i.e., generator)which produces the radio-frequency electrical energy necessary for theoperation of the electrosurgical pencil. In general, when an operationis performed on a patient with an electrosurgical pencil, electricalenergy from the electrosurgical generator is conducted through theactive electrode to the tissue at the site of the operation and thenthrough the patient to a return electrode. The return electrode istypically placed at a convenient place on the patient's body and isattached to the generator by a conductive material. Typically, thesurgeon activates the controls on the electrosurgical pencil to selectthe modes/waveforms to achieve a desired surgical effect. Typically, the“modes” relate to the various electrical waveforms, e.g., a cuttingwaveform has a tendency to cut tissue, a coagulating wave form has atendency to coagulate tissue, and a blend wave form tends to besomewhere between a cut and coagulate wave from. The power or energyparameters are typically controlled from outside the sterile field whichrequires an intermediary like a circulating nurse to make suchadjustment.

A typical electrosurgical generator has numerous controls for selectingan electrosurgical output. For example, the surgeon can select varioussurgical “modes” to treat tissue: cut, blend (blend levels 1-3), lowcut, desiccate, fulgurate, spray, etc. The surgeon also has the optionof selecting a range of power settings typically ranging from 1-300 W.As can be appreciated, this gives the surgeon a great deal of varietywhen treating tissue. However, so many options also tend to complicatesimple surgical procedures and may lead to confusion. Moreover, surgeonstypically follow preset control parameters and stay within known modesand power settings. Therefore, there exists a need to allow the surgeonto selectively control and easily select and regulate the various modesand power settings utilizing simple and ergonomically friendly controlsassociated with the electrosurgical pencil.

Existing electrosurgical instrument systems allow the surgeon to changebetween two pre-configured settings (i.e., coagulation and cutting) viatwo discrete switches disposed on the electrosurgical pencil itself.Other electrosurgical instrument systems allow the surgeon to incrementthe power applied when the coagulating or cutting switch of theinstrument is depressed by adjusting or closing a switch on theelectrosurgical generator. The surgeon then needs to visually verify thechange in the power being applied by looking at various displays and/ormeters on the electrosurgical generator. In other words, all of theadjustments to the electrosurgical instrument and parameters beingmonitored during the use of the electrosurgical instrument are typicallylocated on the electrosurgical generator. As such, the surgeon mustcontinually visually monitor the electrosurgical generator during thesurgical procedure.

Accordingly, the need exists for electrosurgical instruments which donot require the surgeon to continually monitor the electrosurgicalgenerator during the surgical procedure. In addition, the need existsfor electrosurgical instruments which may be configured such that thepower output can be adjusted without the surgeon having to turn his/hervision away from the operating site and toward the electrosurgicalgenerator.

SUMMARY

The present disclosure is directed to an electrosurgical pencil havingvariable controls. In accordance with one aspect of the presentdisclosure the electrosurgical pencil includes an elongated housing andan electrocautery blade supported within the housing and extendingdistally from the housing. The electrocautery blade is, in turn,connected to a source of electrosurgical energy. The pencil alsoincludes a plurality of activation switches supported on the housing.Each activation switch is configured and adapted to selectively completea control loop extending from the source of electrosurgical energy uponactuation thereof. At least one voltage divider network is alsosupported on the housing. The voltage divider network (hereinafter“VDN”) is electrically connected to the source of electrosurgical energyand controls the intensity of electrosurgical energy being delivered tothe plurality of activation switches.

The VDN preferably includes at least a return control wire is providedfor electrically inter-connecting the electrocautery electrode and thesource of electrosurgical energy. The return control wire transmitsexcess electrosurgical energy from the electrocautery electrode to thesource of electrosurgical energy.

The VDN may further include a plurality of control wires forelectrically inter-connecting a respective activation switch to thesource of electrosurgical energy. Each control wire deliverselectrosurgical energy from the source of electrosurgical energy to theelectrocautery electrode.

Desirably, the voltage network divider includes a slide potentiometeroperatively associated with the housing. The slide potentiometersimultaneously controls the intensity of electrosurgical energydelivered to the plurality of activation switches.

The plurality of activation switches define a first resistor networkdisposed within the housing and the slide potentiometer defines a secondresistor network disposed within the housing.

It is envisioned that the voltage divider network may include analgorithm which stores the last setting for each activation switch. Itis further envisioned that the voltage divider network may include analgorithm which requires the slide potentiometer to be set to zero eachtime the mode of operation of the electrosurgical pencil is changed.

The activation switch or switches is/are preferably configured andadapted to control a waveform duty cycle to achieve a desired surgicalintent. Additional switches may be utilized to control the so-called“mode” of operation, i.e., cut, coagulate, blend, and/or may be utilizedto control the intensity/power.

It is envisioned that the electrosurgical pencil includes three modeactivation switches supported on the housing. Each mode activationswitch preferably delivers a characteristic signal to the source ofelectrosurgical energy which, in turn, transmits a correspondingwaveform duty cycle to the electrosurgical pencil. It is contemplatedthat a first activation switch delivers a first characteristic signal tothe source of electrosurgical energy which, in turn, transmits awaveform duty cycle which produces a cutting effect. The secondactivation switch delivers a second characteristic signal to the sourceof electrosurgical energy which, in turn, transmits a waveform dutycycle which produces a blending effect. The third activation switchdelivers a third characteristic signal to the source of electrosurgicalenergy which, in turn, transmits a waveform duty cycle which produces acoagulating effect.

It is envisioned that a single VDN may be supported on the housing. TheVDN is preferably configured and adapted to adjust the intensity orpower of the waveform duty cycle corresponding to a particularactivation switch. The VDN advantageously includes a plurality ofintensity settings. For typical monopolar applications, the VDN may beconfigured and adapted to vary the current intensity at 2K ohms from aminimum of about 60 mA to a maximum of about 240 mA, and morepreferably, from a minimum of about 100 mA to a maximum of about 200 mAat 2K ohms.

The VDN can be slidably supported on the housing. As such, the VDN isset to a minimum when the VDN is placed at a first position, e.g.,distal-most, and is set to a maximum when the VDN is placed at a secondposition, proximal-most or vice versa. The VDN is also positionable atvarying places therebetween. The VDN may also be configured and adaptedto provide a plurality of incremental (i.e., discreet) intensitysettings or may be variable through a range. Alternatively, the VDN maybe rotatably supported on the housing.

It is envisioned that the electrode may be a blade, needle, loop orball. It is also envisioned that the VDN may be a slide potentiometerand include a pair of nubs slidably supported, one each, on either sideof the plurality of activation switches, wherein the potentiometer isoperable from either side of the electrosurgical instrument for use byambidextrous users.

It is further envisioned that the housing may include a recess formed inthe outer surface thereof, and wherein the plurality of activationswitches and the nubs of the at least one voltage divider network aredisposed within the recess.

Desirably, the electrosurgical pencil includes a molded hand gripoperatively supported on the housing. The hand grip is preferably shapedand dimensioned to reduce fatigue on the hand of the user.

According to another aspect of the present disclosure, anelectrosurgical pencil is provide and includes an elongate housing andan electrocautery end effector supported within the housing andextending distally from the housing. The electrosurgical pencil alsoincludes a plurality of activation switches supported on the housing,wherein each activation switch is configured and adapted to energize theend effector with electrosurgical energy. The pencil still furtherincludes at least one VDN supported on the housing which is configuredand adapted to control the intensity of the electrosurgical energy beingdelivered to the electrocautery blade.

Each activation switch is configured and adapted to energize the endeffector with a waveform duty cycle to achieve a desired surgicalintent. Preferably, the electrosurgical pencil includes three modeactivation switches supported on the housing, wherein each of the threemode activation switches is configured and adapted to deliver acharacteristic signal (voltage or current level, impedance, capacitance,inductance and/or frequency) to a source of electrosurgical energy whichsource of electrosurgical energy in turn transmits a correspondingwaveform duty cycle to the end effector. A first activation switchactivates a waveform duty cycle which produces a dissecting effect, asecond activation switch activates a waveform duty cycle which producesa dissecting and hemostatic effect, and a third activation switchactivates a waveform duty cycle which produces a hemostatic effect.These effects have been typically referred to as cut, blend, andcoagulation effects or modes.

It is envisioned that the VDN may include a pair of nubs slidablysupported on the housing, one each, on either side of the activationswitches. It is also contemplated that the VDN may be configured as arheostat wherein, the VDN has a first position corresponding to aminimum intensity, a second position corresponding to a maximumintensity and a plurality of other positions corresponding tointensities between the minimum and the maximum intensity.

It is contemplated that the waveform duty cycle of the activationswitches varies with a change in intensity produced by the VDN.

These and other objects will be more clearly illustrated below by thedescription of the drawings and the detailed description of thepreferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention, andtogether with a general description of the invention given above, andthe detailed description of the embodiments given below, serve toexplain the principles of the invention.

FIG. 1 is a perspective view of an electrosurgical pencil in accordancewith the present disclosure;

FIG. 2 is a partially broken away perspective view of theelectrosurgical pencil of FIG. 1;

FIG. 3 is an exploded perspective view of the electrosurgical pencil ofFIGS. 1 and 2;

FIG. 4 is a perspective view of an electrosurgical pencil in accordancewith another embodiment of the present disclosure;

FIG. 5 is a top plan view of the electrosurgical pencil of FIG. 4;

FIG. 6 is a side elevational view of the electrosurgical pencil of FIGS.4 and 5;

FIG. 7 is a partially broken away, side elevational view of theelectrosurgical pencil of FIGS. 4-6;

FIG. 8 is a front elevational view of the electrosurgical pencil ofFIGS. 4-7;

FIG. 9 is a side elevational view of an electrosurgical pencil accordingto another embodiment of the present disclosure;

FIG. 10 is a top plan view of the electrosurgical pencil of FIG. 9;

FIG. 11 is a front perspective view of a distal end portion of anelectrosurgical pencil according to yet another embodiment of thepresent disclosure;

FIG. 12 is a front perspective view of a distal end portion of anelectrosurgical pencil according to still another embodiment of thepresent disclosure;

FIG. 13 is an enlarged perspective view of a portion of anelectrosurgical pencil illustrating a set of exemplary switches disposedthereon;

FIG. 14 is an enlarged perspective view of a portion of anelectrosurgical pencil illustrating another set of exemplary switchesdisposed thereon;

FIG. 15 is a perspective view of the switch of FIG. 14;

FIG. 16 is a schematic illustration of the voltage divider network ofthe present disclosure;

FIG. 17 is a front elevational view of an electrosurgical generator ofthe present disclosure;

FIG. 18 is a flow chart of a mode of operation of the electrosurgicalpencil of FIGS. 1-3;

FIG. 19 is a power setting look-up table for the electrosurgicalgenerator of FIG. 17, for use with the electrosurgical pencil of FIGS.1-3;

FIG. 20 is an electrical current look-up table for the electrosurgicalgenerator of FIG. 17, for use with the electrosurgical pencil of FIGS.1-3;

FIG. 21 is an output look-up table for the electrosurgical generator ofFIG. 17, for use with the electrosurgical pencil of FIGS. 1-3; and

FIG. 22 is a Mode and Power Display versus Power for the electrosurgicalgenerator of FIG. 17, for use with the electrosurgical pencil of FIGS.1-3.

DETAILED DESCRIPTION

Preferred embodiments of the presently disclosed electrosurgical pencilwill now be described in detail with reference to the drawing figureswherein like reference numerals identify similar or identical elements.As used herein, the term “distal” refers to that portion which isfurther from the user while the term “proximal” refers to that portionwhich is closer to the user or surgeon.

FIG. 1 sets forth a perspective view of an electrosurgical pencilconstructed in accordance with one embodiment of the present disclosureand generally referenced by numeral 10. While the following descriptionwill be directed towards electrosurgical pencils it is envisioned thatthe features and concepts (or portions thereof) of the presentdisclosure can be applied to any electrosurgical type instrument, e.g.,forceps, suction coagulator, vessel sealers, etc.

As seen in FIGS. 1-3, electrosurgical pencil 10 includes an elongatedhousing 2 configured and adapted to support a blade receptacle 4 at adistal end 3 thereof which, in turn, receives a replaceableelectrocautery end effector 6 in the form of a loop and/or bladetherein. Electrocautery blade 6 is understood to include a planar blade,a loop, a needle and the like. A distal end portion 8 of blade 6 extendsdistally from receptacle 4 while a proximal end portion 11 (see FIG. 3)of blade 6 is retained within distal end 3 of housing 2. It iscontemplated that electrocautery blade 6 is fabricated from a conductivetype material, such as, for example, stainless steel, or is coated withan electrically conductive material.

As shown, electrosurgical pencil 10 is coupled to a conventionalelectrosurgical generator “G” via a cable 12. Cable 12 includes atransmission wire 14 (see FIG. 3) which electrically interconnectselectrosurgical generator “G” with proximal end portion 11 ofelectrocautery blade 6. Cable 12 further includes control wires 16 whichelectrically interconnect mode activation switches (as will be describedin greater detail below), supported on an outer surface 7 of housing 2,with electrosurgical generator “G”. For the purposes herein the terms“switch” or “switches” includes electrical actuators, mechanicalactuators, electromechanical actuators (rotatable actuators, pivotableactuators, toggle-like actuators, buttons, etc.) or optical actuators.

Turning back to FIGS. 1-3, as mentioned above, electrosurgical pencil 10further includes at least one activation switch, preferably threeactivation switches 24 a-24 c, each of which are supported on an outersurface 7 of housing 2. Each activation switch 24 a-24 c is operativelyconnected to a location on a tactile element 26 a-26 c (e.g., asnap-dome is shown) which, in turn, controls the transmission of RFelectrical energy supplied from generator “G” to electrosurgical blade6. More particularly, tactile elements 26 a-26 c are operativelyconnected to a voltage divider network 27 (hereinafter “VDN 27”) whichforms a switch closure (e.g., here shown as a film-type potentiometer).For the purposes herein, the term “voltage divider network” relates toany known form of resistive, capacitive or inductive switch closure (orthe like) which determines the output voltage across a voltage source(e.g., one of two impedances) connected in series. A “voltage divider”as used herein relates to a number of resistors connected in serieswhich are provided with taps at certain points to make available a fixedor variable fraction of the applied voltage.

In use, depending on which activation switch 24 a-24 c is depressed arespective switch 26 a-26 c is pressed into contact with VDN 27 and acharacteristic signal is transmitted to electrosurgical generator “G”via control wires 16. Control wires 16 a-16 c are preferablyelectrically connected to switches 26 a-26 c via a terminal 15 (seeFIGS. 2 and 3) operatively connected to VDN 27. By way of example only,electrosurgical generator “G” may be used in conjunction with the devicewherein generator “G” includes a circuit for interpreting and respondingto the VDN settings.

Activation switches 24 a-24 c are configured and adapted to control themode and/or “waveform duty cycle” to achieve a desired surgical intent.For example, first activation switch 24 a can be set to deliver acharacteristic signal to electrosurgical generator “G” which in turntransmits a duty cycle and/or waveform shape which produces a cuttingand/or dissecting effect/function. Meanwhile, second activation switch24 b can be set to deliver a characteristic signal to electrosurgicalgenerator “G” which in turn transmits a duty cycle and/or waveform shapewhich produces a blending effect/function (e.g., a combination of adissecting and a hemostatic effect/function). Finally, third activationswitch 24 c can be set to deliver a characteristic signal toelectrosurgical generator “G” which in turn transmits a duty cycleand/or waveform shape which produces a hemostatic effect/function.

Fourth control wire 16 d (i.e., a return control wire) is preferablyconnected to proximal end 11 of electrocautery blade 6. This preventselectrosurgical current, induced in control wires 16 a-16 c, fromflowing through activation switches 24 a-24 c to electrocautery blade 6.This in turn, increases the longevity and life of switches 24 a-24 c.

As such, switches 24 a-24 c may be selected which are less complexand/or which are relatively inexpensive since the switch does not haveto transmit current during activation. For example, if fourth controlwire 16d is provided, switches 24 a-24 b may be constructed by printingconductive ink on a plastic film. On the other hand, if a fourth controlwire 16 d is not provided, switches may be of the type made of standardstamped metal which add to the overall complexity and cost of theinstrument.

With reference to FIG. 16, in accordance with an embodiment of thepresent disclosure, a voltage divider network (VDN) 27, forinter-connecting control wires 16 a-16 d to activation andelectrosurgical switches 24 a-24 c and electrocautery power wire 14 toblade 6, is shown. VDN 27 includes a first transmission line 27 a,electrically connected to one of control wires 16 a-16 d, for examplecontrol wire 16 a, to operate the various modes of electrosurgicalpencil 10. VDN 27 includes a second transmission line 27 b, electricallyconnected to one of control wires 16 a-16 d, for example control wire 16b, to operate the various intensities of electrosurgical pencil 10. VDN27 includes a third and fourth transmission line 27 c and 27 d,respectively, to apply a voltage across VDN 27. For example, thirdtransmission line 27 c may be isolated or grounded and transmission line27 d may transmit +5 volts.

By way of example only, VDN 27 may include a plurality of resistors “R1”(e.g., 6 resistors), connected in a first series between transmissionline 27 c and transmission line 27 d. Preferably, resistors “R1” combineto total about 1000 ohms of resistance. The first series of resistors“R1” are substantially each separated by a first set of switches “S1”.Preferably, each switch of the first set of switches “S1” iselectrically connected between adjacent resistors “R1” and transmissionline 27 a of VDN 27. In operation, depending on which switch or switchesof the first set of switches “S1” is/are closed, a different mode ofoperation for electrosurgical pencil 10 is activated.

Additionally, by way of example only, VDN 27 may include a plurality ofresistors “R2” (e.g., 4 resistors), connected in a second series betweentransmission line 27 c and transmission line 27 d. Preferably, resistors“R2” combine to total about 1000 ohms of resistance. The second seriesof resistors “R2” are each separated by a second set of switches “S2”.Preferably, each switch of the second set of switches “S2” iselectrically connected between adjacent resistors “R2” and transmissionline 27 b of VDN 27. In operation, depending on which switch or switchesof the second set of switches “S2” is/are closed, a different intensityof RF energy is transmitted by electrosurgical pencil 10.

Also as depicted in FIG. 16, transmission wire 14 is isolated from orotherwise completely separate from VDN 27. In particular, transmissionwire 14 extends directly from the RF input or generator “G” to the RFoutput or to electrocautery blade 6.

The hemostatic effect/function can be defined as having waveforms with aduty cycle from about 1% to about 12%. The blending effect/function canbe defined as having waveforms with a duty cycle from about 12% to about75%. The cutting and/or dissecting effect/function can be defined ashaving waveforms with a duty cycle from about 75% to about 100%. It isimportant to note that these percentages are approximated and may becustomized to deliver the desired surgical effect for various tissuetypes and characteristics.

Electrosurgical pencil 10 further includes an intensity controller 28slidingly supported on housing 2. Intensity controller 28 includes apair of nubs 29 a, 29 b which are slidingly supported, one each, inrespective guide channels 30 a, 30 b, formed in outer surface 7 ofhousing 2 on either side of activations switches 24 a-24 c. By providingnubs 29 a, 29 b on either side of activation switches 24 a-24 c,controller 28 can be easily manipulated by either hand of the user orthe same electrosurgical pencil can be operated by a right-handed or aleft-handed user.

Preferably, intensity controller 28 is a slide potentiometer whereinnubs 29 a, 29 b have a first position (e.g., proximal-most positionclosest to cable 12) corresponding to a relative low intensity setting,a second position (e.g., a distal-most position closest toelectrocautery end effector 6) corresponding to a relative highintensity setting, and a plurality of intermediate positionscorresponding to intermediate intensity settings. As can be appreciated,the intensity settings from proximal end to distal end may be reversedas well, e.g., high to low. It is contemplated that nubs 29 a, 29 b ofintensity controller 28 and corresponding guide channels 30 a, 30 b maybe provided with a series of cooperating discreet or dented positionsdefining a series of positions, preferably five, to allow easy selectionof the output intensity from the low intensity setting to the highintensity setting. The series of cooperating discreet or detentedpositions also provide the surgeon with a degree of tactile feedback. Asbest seen in FIG. 2, intensity controller 28 can include a series ofindicia 31 provided thereon which are visible through guide channels 30a, 30 b. Indicia 31 are preferably a series of numbers (e.g., numbers1-5) which reflect the level of intensity that is to be transmitted.Alternatively, level indicators may be printed alongside the sides ofguide channels 30 a, 30 b along which nubs 29 a, 29 b slide.

Intensity controller 28 is configured and adapted to adjust the powerparameters (e.g., voltage, power and/or current intensity) and/or thepower verses impedance curve shape to affect the perceived outputintensity. For example, the greater intensity controller 28 is displacedin a distal direction the greater the level of the power parameterstransmitted to electrocautery blade 6. Conceivably, current intensitiescan range from about 60 mA to about 240 mA when using an electrosurgicalblade and having a typical tissue impedance of about 2K ohms. Anintensity level of 60 mA provides very light and/or minimalcutting/dissecting/hemostatic effects. An intensity level of 240 mAprovides very aggressive cutting/dissecting/hemostatic effects.Accordingly, the preferred range of current intensity is from about 100mA to about 200 mA at 2K ohms.

The intensity settings are preferably preset and selected from a look-uptable based on a choice of electrosurgical instruments/attachments,desired surgical effect, surgical specialty and/or surgeon preference.The selection may be made automatically or selected manually by theuser. The intensity values may be predetermined or adjusted by the user.

In operation and depending on the particular electrosurgical functiondesired, the surgeon depresses one of activation switches 24 a-24 c, inthe direction indicated by arrow “Y” (see FIG. 1) thereby urging acorresponding switch 26 a-26 c against VDN 27 and thereby transmitting arespective characteristic signal to electrosurgical generator “G”. Forexample, the surgeon can depress activation switch 24 a to perform acutting and/or dissecting function, activation switch 24 b to perform ablending function, or activation switch 24 c to perform a hemostaticfunction. In turn, generator “G” transmits an appropriate waveformoutput to electrocautery blade 6 via transmission wire 14.

In order to vary the intensity of the power parameters ofelectrosurgical pencil 10, the surgeon displaces intensity controller 28in the direction indicated by double-headed arrow “X”. As mentionedabove, the intensity can be varied from approximately 60 mA for a lighteffect to approximately 240 mA for a more aggressive effect. Forexample, by positioning nubs 29 a, 29 b of intensity controller 28closer to the proximal-most end of guide channels 30 a, 30 b (i.e.,closer to cable 12) a lower intensity level is produced and bypositioning nubs 29 a, 29 b of intensity controller 28 closer to thedistal-most end of guide channels 30 a, 30 b (i.e., closer toelectrocautery end effector 6) a larger intensity level is producedresulting in a more aggressive effect being produced. It is envisionedthat when nubs 29 a, 29 b of intensity controller 28 are positioned atthe proximal-most end of guide channels 30 a, 30 b, VDN 27 is set to anull and/or open position. Preferably, electrosurgical pencil 10 isshipped with intensity controller 28 set to the null and/or openpositions.

Preferably, intensity controller 28 controls the intensity level of theelectrosurgical energy transmitted by all three activation switches 24a-24 c, simultaneously. In other words, as nubs 29 a, 29 b of intensitycontroller 28 are positioned relative to guide channels 30 a, 30 b, theintensity level of the electrosurgical energy transmitted to all threeactivation switches 24 a-24 c is set to the same value of slidepotentiometer or intensity controller 28.

As a safety precaution, it is envisioned that when electrosurgicalpencil 10 is changed from one mode to another, intensity controller 28may be configured such that it must be reset (i.e., nubs 29 a, 29 b,re-positioned to the proximal-most end of guide channels 30 a, 30 b thussetting VDN 27 to the null and/or open position). After being reset,intensity controller 28 may be adjusted as needed to the desired and/ornecessary intensity level for the mode selected.

It is envisioned and contemplated that VDN 27 may also include analgorithm which stores the last intensity level setting for each mode.In this manner, intensity controller 28 does not have to be reset to thelast operative value when the particular mode is re-selected.

The combination of placing VDN 27 and fourth control wire 16 d inelectrosurgical pencil 10 essentially places the entire resistor networkof the electrosurgical system (e.g., electrosurgical pencil 10 and thesource of electrosurgical energy “G”) within electrosurgical pencil 10.Conventional electrosurgical systems typically include a currentlimiting resistor disposed within the electrosurgical pencil, foractivating the electrosurgical pencil, and a second resistor networkdisposed in the source of electrosurgical energy, for controlling theintensity of the electrosurgical energy transmitted. In accordance withthe present disclosure, both the first and the second resistor networksare disposed within electrosurgical pencil 10, namely, the firstresistor network as evidenced by activation switches 24 a-24 c, and thesecond resistor network as evidenced by intensity controller 28.

As described above, intensity controller 28 can be configured andadapted to provide a degree of tactile feedback. Alternatively, audiblefeedback can be produced from intensity controller 28 (e.g., a “click”),from electrosurgical energy source “G” (e.g., a “tone”) and/or from anauxiliary sound-producing device such as a buzzer (not shown).

Preferably, as seen in FIGS. 1 and 3, intensity controller 28 andactivation switches 24 a-24 c are supported in a recess 9 formed inouter wall 7 of housing 2. Desirably, activation switches 24 a-24 c arepositioned at a location where the fingers of the surgeon would normallyrest when electrosurgical pencil 10 is held in the hand of the surgeonwhile nubs 29 a, 29 b of intensity controller 28 are placed at locationswhich would not be confused with activation switches 24 a-24 c.Alternatively, nubs 29 a, 29 b of intensity controller 28 are positionedat locations where the fingers of the surgeon would normally rest whenelectrosurgical pencil 10 is held in the hand of the surgeon whileactivation switches 24 a-24 c are placed at locations which would not beconfused with nubs 29 a, 29 b of intensity controller 28. In addition,recess 9 formed in outer wall 7 of housing 2 advantageously minimizesinadvertent activation (e.g., depressing, sliding and/or manipulating)of activation switches 24 a-24 c and intensity controller 28 while inthe surgical field and/or during the surgical procedure.

As seen in FIG. 3, electrosurgical pencil 10 includes a molded/contouredhand grip 5 which substantially surrounds the distal and proximal endsof housing 2 as well as the underside of housing 2. Contoured hand grip5 is shaped and dimensioned to improve the handling of electrosurgicalpencil 10 by the surgeon. Accordingly, less pressure and gripping forceis required to use and/or operate electrosurgical pencil 10 therebypotentially reducing the fatigue experienced by the surgeon and toprevent movement of electrosurgical pencil 10 during proximal and distaladjustments of nubs 29 a and 29 b.

Turning now to FIGS. 4-8, an electrosurgical pencil constructed inaccordance with another embodiment of the present disclosure is showngenerally as 100. Electrosurgical pencil 100 includes at least oneactivation switch, preferably three activation switches 124 a-124 c,each of which are supported on an outer surface 107 of housing 102. Eachactivation switch 124 a-124 c is operatively connected to a respectiveswitch 126 a-126 c which, in turn, controls the transmission of RFelectrical energy supplied from generator “G” to electrosurgical blade106. More particularly, switches 126 a-126 c are electrically coupled tocontrol loop 116 and are configured to close and/or complete controlloop 116 to thereby permit RF energy to be transmitted to electrocauteryblade 106 from electrosurgical generator “G”.

Activation switches 124 a-124 c are configured and adapted to controlthe mode and/or “waveform duty cycle” to achieve a desired surgicalintent in the same manner as activation switches 24 a-24 c ofelectrosurgical pencil 10 described above.

Electrosurgical pencil 100 further includes at least one intensitycontroller, preferably two intensity controllers 128 a and 128 b, eachof which are slidingly supported in guide channels 130 a, 130 b,respectively, which are formed in outer surface 107 of housing 102.Preferably, each intensity controller 128 a and 128 b is a slide-likepotentiometer. It is contemplated that each intensity controller 128 aand 128 b and respective guide channel 130 a and 130 b may be providedwith a series of cooperating discreet or detented positions defining aseries of positions, preferably five, to allow easy selection of outputintensity from a minimum amount to a maximum amount. The series ofcooperating discreet or detented positions also provide the surgeon witha degree of tactile feedback. It is further envisioned that one of theseries of positions for intensity controllers 128 a, 128 b is an offposition (i.e., no level of electrical or RF energy is beingtransmitted).

Intensity controllers 128 a, 128 b is configured and adapted to adjustone of the power parameters (e.g., voltage, power and/or currentintensity) and/or the power verses impedance curve shape to affect theperceived output intensity.

For example, the greater intensity controllers 128 a, 128 b aredisplaced in a distal direction (i.e., in the direction ofelectrocautery blade 106) the greater the level of the power parameterstransmitted to electrocautery blade 106. Conceivably, currentintensities can range from about 60 mA to about 240 mA when using anelectrosurgical blade and having a typical tissue impedance of about2000 ohms. An intensity level of 60 mA provides very light and/orminimal cutting/dissecting/hemostatic effects. An intensity level of 240mA provides very aggressive cutting/dissecting/hemostatic effects.Accordingly, the preferred range of current intensity is from about 100mA to about 200 mA at 2K ohms.

The intensity settings are preferably preset and selected from a look-uptable based on a choice of electrosurgical instruments/attachments,desired surgical effect, surgical specialty and/or surgeon preference.The selection may be made automatically or selected manually by theuser. The intensity values may be predetermined or adjusted by the user.

In operation and depending on the particular electrosurgical functiondesired, the surgeon depresses one of activation switches 124 a-124 c,in the direction indicated by arrow “Y” (see FIGS. 4 and 7) therebyclosing a corresponding switch 126 a-126 c and closing and/or completingcontrol loop 116. For example, the surgeon can depress activation switch124 a to perform a cutting or dissecting function, activation switch 124b to perform a dissecting/hemostatic function, or activation switch 124c to perform a hemostatic function. In turn, generator “G” transmits anappropriate waveform output to electrocautery blade 106 via transmissionwire 114.

In order to vary the intensity of the power parameters ofelectrosurgical pencil 100, preferably, the current intensity, thesurgeon displaces at least one of intensity controllers 128 a, 128 b inthe direction indicated by double-headed arrow “X”. As mentioned above,the intensity can be varied from approximately 60 mA for a light effectto approximately 240 mA for a more aggressive effect. For example, bypositioning one of intensity controllers 128 a, 128 b closer to theproximal-most end (i.e., closer to cable 112) a light effect is producedand by positioning one of intensity controllers 128 a, 128 b closer tothe distal-most end (i.e., closer to electrocautery blade 106) a moreaggressive effect is produced. As described above, each intensitycontroller 128 a, 128 b can be configured and adapted to provide adegree of tactile feedback. Alternatively, audible feedback can beproduced from each intensity controller 128 a, 128 b (e.g., a “click”),electrosurgical energy source “G” (e.g., a “tone”) and/or an auxiliarysound-producing device such as a buzzer (not shown).

In an alternative embodiment, as seen in FIGS. 9 and 10, slidingintensity controllers 128 a, 128 b have been replaced with intensitycontrollers 228 a, 228 b in the form of dial-like VDNs. Intensitycontrollers 228 a, 228 b function to vary the intensity of the powerparameters via a rotation of dial controllers 228 a, 228 b in either aclockwise or counter-clockwise direction as indicated by double headedarrow “Z”. As seen in FIGS. 6 and 7, dial controllers 228 a, 228 b aredisposed externally of housing 102, however, it is contemplated thatdial controllers 228 a, 228 b are disposed within housing 102 with onlya portion projecting therefrom for manipulation by the surgeon. It isenvisioned that intensity controllers 228 a, 228 b can be a singlecontroller having a pair of opposed knobs/dials provided, one each, oneither side of housing 102. In this manner, the intensity can becontrolled from either side of electrosurgical pencil 100.

Since the surgeon has a number of controls at his finger tips, thesurgeon is able to create a pallet of varying therapeutic effectsranging from a pure “cutting” effect to a pure “coagulating” effect anda number of effects in between at a number of intensities. Moreover,with some pre-setting of the electrosurgical energy source “G”,electrosurgical pencil 100 will have all the useful settings availableto the surgeon within the sterile field. Accordingly, it is notnecessary that the surgeon interact with hardware outside the sterilefield (e.g., electrosurgical energy source “G”) once the surgicalprocedure begins thus allowing the surgeon to focus attention on thesurgical procedure.

While embodiments of electrosurgical pencils according to the presentdisclosure have been described herein, it is not intended that thedisclosure be limited there and the above description should beconstrued as merely exemplifications of preferred embodiments. Thoseskilled in the art will envision other modifications within the scopeand spirit of the present disclosure.

For example, as seen in FIG. 11, an alternative embodiment of anelectrosurgical pencil is shown generally as 200. Electrosurgical pencil200 is similar to electrosurgical pencil 10 and/or 100 and will only bediscussed in detail to the extent necessary to identify differences inconstruction and operation. As seen in FIG. 11, electrosurgical pencil200 includes a plurality of nubs, preferably, three nubs, 229 a-229 cwhich are slidingly supported, one each, in respective guide channels230 a-230 c, formed in outer surface 7 of housing 2, at a positionproximal of activation switches 24 a-24 c. Each nub 229 a-229 c isoperatively engaged with a slide potentiometer.

Accordingly, electrosurgical pencil 200 can be configured such that eachactivation switch 24 a-24 c is a separate mode, such as, for example,activation switch 24 a can be set such that electrosurgical pencil 200performs “division” when depressed, activation switch 24 b can be setsuch that electrosurgical pencil 200 performs “division with hemostasis”when depressed, and activation switch 24 c can be set such thatelectrosurgical pencil 200 performs “hemostasis” when depressed. Inaddition, each nub 229 a-229 c is in operative engagement with acorresponding activation switch 24 a-24 c such that the power for eachmode of operation of electrosurgical pencil 200 can be independentlyadjusted.

As seen in FIG. 12, nubs 229 a-229 c of electrosurgical pencil 200 havebeen replaced with toggles 231 a-231 c operatively engaged with arespective activation switch 24 a-24 c. Each toggle 231 a-231 c can beoperatively engaged with a rocker-type switch (not shown) or arotational dial (not shown) in place of the slide-type potentiometerdescribed above.

Turning now to FIGS. 13-15, an electrosurgical pencil, in accordancewith still another embodiment of the present disclosure, is generallydesignated as 300. Electrosurgical pencil 300 is similar toelectrosurgical pencil 10 and/or 100 and will only be discussed indetail to the extent necessary to identify differences in constructionand operation. As seen in FIGS. 13 and 14, nubs 29 a, 29 b have beenreplaced with a dial 329 rotatably supported in an aperture 330 formedin outer surface 7 of housing 2. Preferably, dial 329 is positionedforward of activation switch 24 a such that dial 329 is notinadvertently rotated during the depression of any one of activationswitches 24 a-24 c.

As seen in FIG. 13, a side surface 331 of dial 329 can be provided withindicia and/or markings “M” in the form of a scale and/or other form ofgradient to indicate to the surgeon the degree of and/or level of powerat which electrosurgical pencil 300 is set.

As seen in FIGS. 14 and 15, windows 332 can be formed on either side ofdial 329 in outer surface 7 of housing 2. As seen in FIG. 15, windows332 provide the surgeon with visibility to indicia “M” provided on stub333 extending from the central axis of dial 329. Indicia “M” can be inthe form of numbers, letters, colors and, as seen in FIGS. 14 and 15, anenlarging gradient. It is envisioned that each dial 329 can perform adual function, for example, dial 329 can be rotated to set the desiredpower level and can be pressed down to activate the electrosurgicalpencil with the desired mode.

Tuming now to FIG. 17, an electrosurgical generator in accordance withan embodiment of the present disclosure, is shown generally as “G”.Electrosurgical generator “G” includes a plurality of displays 402, hereshown with three displays, 402 a-402 c. Each of displays 402 a-402 c mayinclude a number of screens, windows or tabs as depicted by numerals 404a-404 c.

Each screen 404 a-404 c of each display 402 a-402 c may include a numberof display elements 406. By way of example only, as seen in FIG. 17,screen 404 b of display 402 a includes at least three display elements406 a-406 c. Display element 406 a may show the mode and power settingof electrosurgical generator “G” to be transmitted to electrosurgicalpencil 10. Display element 406 b may show a range or bar setting ofelectrosurgical generator “G” to be transmitted to electrosurgicalpencil 10. Display element 406 c may show the position of the slider onelectrosurgical pencil 10.

Turning now to FIGS. 18-22, a flow chart (FIG. 18) depicting a method ofusing electrosurgical pencil 10 with electrosurgical generator “G” ofFIG. 17, for a plurality of settings (FIGS. 19-22), is shown and will bedescribed. Initially, the bar level or setting of electrosurgicalgenerator “G” is selected by the user. By way of example only, as seenin FIGS. 17, 19 and 20, electrosurgical generator “G” includes five (5)levels or settings, although other numbers of levels or settings arepossible. By selecting a particular bar level or setting,electrosurgical generator “G” is set to deliver power and current, foreach mode of operation, at predetermined levels, as seen in the tablesof FIGS. 19 and 20.

With the bar level or setting selected, as needed or desired, as seen inFIG. 18, the user sets intensity controller 28 (FIG. 2) by sliding nub29 a and/or 29 b to one of a number of positions along guide channels 30a, 30 b of electrosurgical pencil 10. While nubs 29 a, 29 b of intensitycontroller 28 are shown and described as being settable to five (5)positions along electrosurgical pencil 10, it is envisioned and withinthe scope of the present disclosure that electrosurgical pencil 10 maybe configured to provide more or fewer than five (5) settable positionsfor nubs 29 a, 29 b of intensity controller 28. By positioning intensitycontroller 28 to a particular setting, electrosurgical generator “G” isset to deliver power and current for each mode of operation, at apredetermined level, as seen in the tables of FIGS. 19 and 20.

With the bar level or setting selected and intensity controller 28 set,as seen in FIG. 18, the necessary or desired mode of operation ofelectrosurgical pencil 10 is activated by depressing the appropriate orcorresponding activation switch 24 a-24 c (FIG. 1). As described above,if switch 24 a is depressed, then the cut mode is activated, if switch24 b is depressed, then the blend or dividing mode is activated, and ifswitch 24 c is depressed, then the coagulating mode is activated.

For example, as seen in FIG. 19, if the bar level or setting ofelectrosurgical generator “G” is set to “2” and the position ofintensity controller 28 is set to “4”, then the power value for eachmode of operation is as follows: 150 watts in Mode 1 for cutting; 100watts in Mode 2 for blending or dividing; and 60 watts in Mode 3 forcoagulating. Additionally, the electrical current value for thisparticular setting, as seen in FIG. 20, is as follows: 0.625 amps inMode 1 for cutting; 0.500 amps in Mode 2 for blending or dividing; and0.500 amps in Mode 3 for coagulating.

As seen in FIG. 21, the output frequency and duty cycle for each mode ofoperation is shown. Also shown in FIG. 21 is a summary of the variouselectrical current settings, from FIG. 20, for each mode of operation,for each position of intensity controller 28 of electrical pencil 10,when the bar or level setting for electrosurgical generator “G” is setto “2”.

In FIG. 22, a summary of the various power settings, from FIG. 19, foreach mode of operation, for each position of intensity controller 28 ofelectrical pencil 10, when the bar or level setting for electrosurgicalgenerator “G” is set to “2”, is shown.

It is further envisioned that any of the electrosurgical pencilsdisclosed herein can be provided with a lock-out mechanism/system (notshown) wherein when one of the activation switches is depressed, theother remaining activation switches can either not be depressed or cannot cause transmission of electrosurgical energy to electrocautery blade106.

It is also envisioned that the electrosurgical pencil 100 may include asmart recognition technology which communicates with the generator toidentify the electrosurgical pencil and communicate various surgicalparameters which relate to treating tissue with electrosurgical pencil100. For example, the electrosurgical pencil 100 may be equipped with abar code or Aztec code which is readable by the generator and whichpresets the generator to default parameters associated with treatingtissue with electrosurgical pencils. The bar code or Aztec code may alsoinclude programmable data which is readable by the generator and whichprograms the generator to specific electrical parameters prior to use.

Other smart recognition technology is also envisioned which enable thegenerator to determine the type of instrument being utilized or toinsure proper attachment of the instrument to the generator as a safetymechanism. One such safety connector is identified in U.S. patentapplication Ser. No. 10/718,114, filed Nov. 20, 2003, the entirecontents of which being incorporated by reference herein. For example,in addition to the smart recognition technology described above, such asafety connector can include a plug or male portion operativelyassociated with the electrosurgical pencil and a complementary socket orfemale portion operatively associated with the electrosurgicalgenerator. Socket portion is “backward compatible” to receive connectorportions of electrosurgical pencils disclosed therein and to receiveconnector portions of prior art electrosurgical instruments.

It is also envisioned that the current controls may be based on currentdensity or designed to deliver a specific current for a defined surfacearea (amp/cm²).

Although the subject apparatus has been described with respect topreferred embodiments, it will be readily apparent, to those havingordinary skill in the art to which it appertains, that changes andmodifications may be made thereto without departing from the spirit orscope of the subject apparatus.

1. An electrosurgical pencil, comprising: an elongated housing; anelectrocautery electrode supported within the housing and extendingdistally from the housing, the electrocautery electrode being connectedto a source of electrosurgical energy; a plurality of activationswitches supported on the housing, each activation switch beingconfigured and adapted to selectively complete a control loop extendingfrom the source of electrosurgical energy upon actuation thereof; and atleast one voltage divider network supported on the housing, the at leastone voltage divider network being electrically connected to the sourceof electrosurgical energy for controlling the intensity ofelectrosurgical energy being delivered to the plurality of activationswitches from the source of electrosurgical energy and for controllingthe intensity of electrosurgical energy delivered to the plurality ofactivation switches returning from the electrocautery electrode, the atleast one voltage divider network comprises at least one return controlwire electrically inter-connecting the electrocautery electrode and thesource of electrosurgical energy, the return control wire transmittingexcess electrosurgical energy from the electrocautery electrode to thesource of electrosurgical energy.
 2. The electrosurgical pencilaccording to claim 1, wherein the at least one voltage divider networkfurther comprises: a plurality of control wires electricallyinter-connecting a respective activation switch to the source ofelectrosurgical energy, each control wire delivering electrosurgicalenergy from the source of electrosurgical energy to the electrocauteryelectrode.
 3. The electrosurgical pencil according to claim 2, whereinthe voltage network divider includes a slide potentiometer operativelyassociated with the housing.
 4. The electrosurgical pencil according toclaim 3, wherein the plurality of activation switches define a firstresistor network disposed within the housing, and wherein the slidepotentiometer defines a second resistor network disposed within thehousing.
 5. The electrosurgical pencil according to claim 4, wherein theslide potentiometer simultaneously controls the intensity ofelectrosurgical energy delivered to the plurality of activationswitches.
 6. The electrosurgical pencil according to claim 5, whereinthe voltage divider network includes an algorithm which stores the lastsetting for each activation switch.
 7. The electrosurgical pencilaccording to claim 6, wherein the voltage divider network includes analgorithm which requires the slide potentiometer to be set to zero eachtime the mode of operation of the electrosurgical pencil is changed. 8.The electrosurgical pencil according to claim 7, wherein at least oneactivation switch is configured and adapted to control a waveform dutycycle to achieve a desired surgical intent.
 9. The electrosurgicalpencil according to claim 8, further including three mode activationswitches supported on the housing.
 10. The electrosurgical pencilaccording to claim 9, wherein each mode activation switch delivers acharacteristic signal to the source of electrosurgical energy which inturn transmits a corresponding waveform duty cycle to theelectrosurgical pencil.
 11. The electrosurgical pencil according toclaim 9, wherein a first activation switch delivers a firstcharacteristic signal to the source of electrosurgical energy which inturn transmits a waveform duty cycle which produces a cutting effect, asecond activation switch delivers a second characteristic signal to thesource of electrosurgical energy which in turn transmits a waveform dutycycle which produces a blending effect, and wherein a third activationswitch delivers a third characteristic signal to the source ofelectrosurgical energy which in turn transmits a waveform duty cyclewhich produces a coagulating effect.
 12. The electrosurgical pencilaccording to claim 11, wherein the voltage divider network is apotentiometer.
 13. The electrosurgical pencil according to claim 12,wherein the potentiometer is a rheostat having discreet values andconfigured and adapted to adjust the intensity of the waveform dutycycle corresponding to a particular activation switch.
 14. Theelectrosurgical pencil according to claim 13, wherein the potentiometerhas a plurality of intensity settings.
 15. The electrosurgical pencilaccording to claim 14, wherein the potentiometer is configured andadapted to vary a current intensity from a minimum of about 60 mA to amaximum of about 240 mA at 2K ohms.
 16. The electrosurgical pencilaccording to claim 14, wherein the potentiometer is configured andadapted to vary a current intensity from a minimum of about 100 mA to amaximum of about 200 mA at 2K ohms.
 17. The electrosurgical pencilaccording to claim 16, wherein the potentiometer is slidably supportedon the housing.
 18. The electrosurgical pencil according to claim 17,wherein the potentiometer is set to a minimum when the potentiometer isplaced at a first position and is set to a maximum when thepotentiometer is placed at a second position.
 19. The electrosurgicalpencil according to claim 18, wherein the potentiometer is configuredand adapted to provide a plurality of discreet intensity settings. 20.The electrosurgical pencil according to claim 1, wherein the at leastone voltage divider network is rotatably supported on the housing. 21.The electrosurgical pencil according to claim 19, wherein theelectrocautery electrode is one of a blade, needle, a loop and a ball.22. The electrosurgical pencil according to claim 19, wherein the slidepotentiometer includes a pair of nubs slidably supported, one each, oneither side of the plurality of activation switches such that thepotentiometer is operable from either side of the electrosurgicalpencil.
 23. The electrosurgical pencil according to claim 22, whereinthe housing includes a recess formed in the outer surface thereof, andwherein the plurality of activation switches and the nubs of the voltagedivider network are disposed within the recess.
 24. The electrosurgicalpencil according to claim 8, further including a molded hand gripoperatively supported on the housing.
 25. The electrosurgical pencilaccording to claim 24, wherein the hand grip is shaped and dimensionedto reduce fatigue on the hand of the user.
 26. The electrosurgicalpencil according to claim 7, wherein the electrosurgical pencil includesthree mode activation switches supported on the housing, wherein each ofthe three mode activation switches is configured and adapted to delivera characteristic signal to a source of electrosurgical energy whichsource of electrosurgical energy in turn transmits a correspondingwaveform duty cycle to the end effector.
 27. The electrosurgical pencilaccording to claim 26, wherein a first mode activation switch activatesa waveform duty cycle which produces a dissecting effect, a second modeactivation switch activates a waveform duty cycle which produces adissecting and hemostatic effect, and a third mode activation switchactivates a waveform duty cycle which produces a hemostatic effect. 28.The electrosurgical pencil according to claim 27, wherein the at leastone voltage divider network includes a pair of nubs slidably supportedon the housing, one each, on either side of the activation switches. 29.The electrosurgical pencil according to claim 28, wherein the at leastone voltage divider network has a first position corresponding to aminimum intensity, a second position corresponding to a maximumintensity and a plurality of positions between the first and secondpositions corresponding to intensities between the minimum and themaximum intensity.
 30. The electrosurgical pencil according to claim 29,wherein the at least one voltage divider network is configured andadapted to vary a current intensity from a minimum of about 60 mA to amaximum of about 240 mA at 2K ohms.
 31. The electrosurgical pencilaccording to claim 30, wherein the at least one voltage divider networkis configured and adapted to vary a current intensity from a minimum ofabout 100 mA to a maximum of about 200 mA.
 32. The electrosurgicalpencil according to claim 31, wherein the at least one voltage dividernetwork is set to the minimum when the at least one voltage dividernetwork is placed at a proximal-most position and is set to the maximumwhen placed at a distal-most position.
 33. The electrosurgical pencilaccording to claim 31, wherein the at least one voltage divider networkis set to the minimum when the at least one voltage divider network isplaced at a distal-most position and is set to the maximum when placedat a proximal-most position.
 34. The electrosurgical pencil according toclaim 32, wherein the at least one voltage divider network is configuredand adapted to provide a plurality of discreet intensity settings. 35.The electrosurgical pencil according to claim 32, wherein the at leastone voltage divider network is configured and adapted to provide analogintensity settings.
 36. The electrosurgical pencil according to claim31, wherein the waveform duty cycle of the activation switches varieswith a change in intensity produced by the at least one voltage dividernetwork.
 37. An electrosurgical pencil, comprising: an elongatedhousing; an electrocautery electrode supported within the housing andextending distally from the housing, the electrocautery electrode beingconnected to a source of electrosurgical energy; a plurality ofactivation switches supported on the housing, each activation switchbeing configured and adapted to selectively complete a control loopextending from the source of electrosurgical energy upon actuationthereof; and at least one voltage divider network supported on thehousing, the at least one voltage divider network being electricallyconnected to the source of electrosurgical energy for controlling theintensity of electrosurgical energy being delivered to theelectrosurgical pencil.
 38. The electrosurgical pencil according toclaim 37, wherein the at least one voltage divider network furthercomprises: a plurality of control wires electrically inter-connectingthe respective activation switch to the source of electrosurgicalenergy, each control wire being isolated within the electrosurgicalpencil from the control wire delivering electrosurgical energy to theelectrocautery electrode.
 39. The electrosurgical pencil according toclaim 38, wherein the voltage network divider includes a slideoperatively associated with the housing.
 40. The electrosurgical pencilaccording to claim 39, wherein the plurality of activation switchesdefine a first resistor network disposed within the housing, and whereinthe slide defines a second resistor network disposed within the housing.41. The electrosurgical pencil according to claim 40, wherein the slidesimultaneously controls the intensity of electrosurgical energydelivered to the plurality of activation switches.
 42. Theelectrosurgical pencil according to claim 41, wherein at least oneactivation switch is configured and adapted to control a waveform dutycycle to achieve a desired surgical intent.
 43. The electrosurgicalpencil according to claim 42, further including three mode activationswitches supported on the housing.
 44. The electrosurgical pencilaccording to claim 43, wherein each mode activation switch delivers acharacteristic signal to the source of electrosurgical energy which inturn transmits a corresponding waveform duty cycle to the electrocauteryelectrode.
 45. The electrosurgical pencil according to claim 43, whereina first activation switch delivers a first characteristic signal to thesource of electrosurgical energy which in turn transmits a waveform dutycycle which produces a cutting effect, a second activation switchdelivers a second characteristic signal to the source of electrosurgicalenergy which in turn transmits a waveform duty cycle which produces ablending effect, and wherein a third activation switch delivers a thirdcharacteristic signal to the source of electrosurgical energy which inturn transmits a waveform duty cycle which produces a coagulatingeffect.
 46. The electrosurgical pencil according to claim 45, wherein anintensity controlling slide is supported in the housing.
 47. Theelectrosurgical pencil according to claim 46, wherein each position onthe slide delivers a characteristic signal to the source ofelectrosurgical energy which in turn adjusts the intensity of thewaveform duty cycle corresponding to a particular activation switch. 48.The electrosurgical pencil according to claim 47, wherein the slide hasa plurality of intensity settings.
 49. The electrosurgical pencilaccording to claim 48, wherein the slide is configured and adapted tovary a current intensity from a minimum of about 60 mA to a maximum ofabout 240 mA at 2K ohms.
 50. The electrosurgical pencil according toclaim 48, wherein the slide is configured and adapted to vary a currentintensity from a minimum of about 100 mA to a maximum of about 200 mA at2K ohms.
 51. The electrosurgical pencil according to claim 50, whereinthe slide is set to a minimum when the potentiometer is placed at afirst position and is set to a maximum when the potentiometer is placedat a second position.
 52. The electrosurgical pencil according to claim37, wherein the at least one voltage divider network is rotatablysupported on the housing.
 53. The electrosurgical pencil according toclaim 51, wherein the electrocautery electrode is one of a blade,needle, a loop and a ball.
 54. The electrosurgical pencil according toclaim 51, wherein the slide potentiometer includes a pair of nubsslidably supported, one each, on either side of the plurality ofactivation switches such that the potentiometer is operable from eitherside of the electrosurgical pencil.
 55. The electrosurgical pencilaccording to claim 54, wherein the housing includes a recess formed inthe outer surface thereof, and wherein the plurality of activationswitches and the nubs of the voltage divider network are disposed withinthe recess.
 56. The electrosurgical pencil according to claim 42,further including a molded hand grip operatively supported on thehousing.
 57. The electrosurgical pencil according to claim 56, whereinthe hand grip is shaped and dimensioned to reduce fatigue on the hand ofthe user.
 58. The electrosurgical pencil according to claim 56, whereinthe hand grip provides traction to prevent movement of the pencil whilechanging the slide.
 59. The electrosurgical pencil according to claim41, wherein the electrosurgical pencil includes three mode activationswitches supported on the housing, wherein each of the three modeactivation switches is configured and adapted to deliver acharacteristic signal to a source of electrosurgical energy which sourceof electrosurgical energy in turn transmits a corresponding waveformduty cycle to the end effector.
 60. The electrosurgical pencil accordingto claim 59, wherein a first mode activation switch activates a waveformduty cycle which produces a dissecting effect, a second mode activationswitch activates a waveform duty cycle which produces a dissecting andhemostatic effect, and a third mode activation switch activates awaveform duty cycle which produces a hemostatic effect.
 61. Theelectrosurgical pencil according to claim 60, wherein the at least onevoltage divider network includes a pair of nubs slidably supported onthe housing, one each, on either side of the activation switches. 62.The electrosurgical pencil according to claim 61, wherein the at leastone voltage divider network has a first position corresponding to aminimum intensity, a second position corresponding to a maximumintensity and a plurality of positions between the first and secondpositions corresponding to intensities between the minimum and themaximum intensity.
 63. The electrosurgical pencil according to claim 62,wherein the at least one voltage divider network is configured andadapted to vary a current intensity from a minimum of about 60 mA to amaximum of about 240 mA at 2K ohms.
 64. The electrosurgical pencilaccording to claim 63, wherein the at least one voltage divider networkis configured and adapted to vary a current intensity from a minimum ofabout 100 mA to a maximum of about 200 mA.
 65. The electrosurgicalpencil according to claim 64, wherein the at least one voltage dividernetwork is set to the minimum when the at least one voltage dividernetwork is placed at a proximal-most position and is set to the maximumwhen placed at a distal-most position.
 66. The electrosurgical pencilaccording to claim 65, wherein the at least one voltage divider networkis set to the minimum when the at least one voltage divider network isplaced at a distal-most position and is set to the maximum when placedat a proximal-most position.
 67. The electrosurgical pencil according toclaim 65, wherein the at least one voltage divider network is configuredand adapted to provide a plurality of discreet intensity settings. 68.The electrosurgical pencil according to claim 65, wherein the at leastone voltage divider network is configured and adapted to provide analogintensity settings.
 69. The electrosurgical pencil according to claim64, wherein the waveform duty cycle of the activation switches varieswith a change in intensity produced by the at least one voltage dividernetwork.
 70. The electrosurgical pencil according to claim 37, whereinan intensity control slide is positioned on the body for each activationbutton.
 71. The electrosurgical pencil according to claim 70, whereineach slide operates a voltage divider network, the voltage dividernetwork produces a characteristic signal on a separate control wire tothe source of electrosurgical energy.